1. Field of Invention
The invention relates to a printing device such as a facsimile machine.
2. Description of Related Art
Conventionally, a facsimile machine, which performs printing by a thermal transfer method, uses ink ribbon wound in a roll.
In the above facsimile machine, a take-up shaft for the ink ribbon is linked to a take-up motor. When the take-up motor is driven, the ink ribbon is wound around the take-up shaft. In this case, the amount of the ink ribbon consumed is calculated based on the number of revolutions of the take-up motor, and stored in memory provided in a ribbon cassette accommodating the ink ribbon. When the contents stored in the memory reach a specified value, it is determined that there is no ribbon remaining, that is, the facsimile machine is out of ribbon. In addition, the facsimile machine has a display unit to show the remaining amount of the ink ribbon.
However, in the facsimile machine, the amount of the ink ribbon consumed is determined based on the number of revolutions of the take-up motor. Therefore, when the ink ribbon is actually used, the remaining amount of the ink ribbon stored in the memory may fall out of synch with that of the ink ribbon actually used. As a result, the display unit may show that the ink ribbon still remains, although it actually has run out.
The invention provides a printing device capable of reliably detecting that the ink ribbon has run out.
In one aspect of the invention, a printing device may include a printing device body, a ribbon cassette that accommodates an ink ribbon and is detachable from the printing device body, an ink ribbon take-up mechanism that takes up the ink ribbon, an ink ribbon usage determining device that determines an amount of the ink ribbon consumed, a recording medium that stores an amount of the ink ribbon remaining, and a ribbon-empty determining device that determines that there is no amount of the ink ribbon remaining. When the ribbon-empty determining device determines that there is no amount of the ink ribbon remaining, it resets the recording medium.
According to the printing device, when it is determined that the ink ribbon has run out, the content of the recording medium is reset. Therefore, even when the ribbon cassette is used thereafter, it is easily recognized that there is no ink ribbon remaining, thereby preventing the user from reusing such a ribbon cassette.